Apply Filter On, Scheduler Subjob Filter

The default setting of this field is Both but the other option is Source Only.
When you run a job of the type NORMAL and the What to do option is set for: Upd./Add/Del. you can set a filter on the job to extract for example only certain parts of a table. When the Both option is selected, the filter will apply to both source and destination tables but if Source only is selected, the filter only applies to the source.